Luminous Landscape Forum
Equipment & Techniques => Digital Cameras & Shooting Techniques => Topic started by: chickenhawk212 on October 25, 2007, 07:17:27 pm
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Recieved a new 40d a few days ago and though ive only shot a few hundred frames so far just wanted to share my experience with everybody.
Image quality is awesome, most of the review sites said it would be great: low noise with wide dynamic range, and it is. What is most striking though is how really really nice it feels, though the changes from my 20d are small, it somehow just feels extremely well put together. This is especially true when comparing to my rebel xt backup body. So so much nicer. Probably the best part is how fast the camera responds: the autofocus is much better, and the buffer size and shooting speed just make the camera feel always ready and instantly responsive. Though ive never used a 1 series camera, this camera feels very much like a well made photographic tool, not some plasticy toy. If you are considering this camera, youll be very happy with the purchase upgrading from an earlier x0d model camera; furthermore, those upgrading from the rebel series will be ecstaticly happy...they are totally different animals.
Good luck all and happy shooting!
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I basically agree but I have found one serious problem area that I need to explore further. With my 1DMKII, I can set the focus button to the * and hold that down in AI Servo mode so the camera will continue to focus on an object, then I can press the shutter button and get high speed firing immediately. With the 40D, when I do this same thing, I often get a seriously long lag before the initial firing starts and often it appears to refuse to fire properly. If I set the shutter button to focus and shutter and hold it down partially to keep focus on moving object, I get no hesitation when I go to fire the shutter. I have not explored the problem with both cameras in the exact same lighting but the fact that the 40D works with shutter-only button properly but not with the * used for focusing is a real potential problem for me. Other than that, I like the camera a lot and if I can solve the * focus / shutter fire problem it will be great. Otherwise....I'll have a 40D on the market.
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Though ive never used a 1 series camera, this camera feels very much like a well made photographic tool, not some plasticy toy. [a href=\"index.php?act=findpost&pid=148710\"][{POST_SNAPBACK}][/a]
Are you saying that your 20D feels like a plasticky toy by comparison?
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Are you saying that your 20D feels like a plasticky toy by comparison?
[a href=\"index.php?act=findpost&pid=148732\"][{POST_SNAPBACK}][/a]
My 40D definitely feels more solid than my 20D, but that may be because my 20D is pretty worn now. In some places that were originally matte, my fingers have polished it smooth. I have no idea how a new 40D compares to a new 20D, but since new 20Ds aren't for sale now, it really doesn't matter.
I agree that the 40D feels generally more responsive, and that the image quality is superior. The 40D definitely has a wider dynamic range and lower noise. Autofocus is substantially improved as well.
I have never experienced the focus delay mentioned above.
A poster on a different forum complained that he wouldn't buy a 40D because it isn't supported in Camera Raw by Photshop CS2. While that is technically correct, you can use the free DNG converter to make DNG files that will work in CS2. Besides, it's not like CS2 will support any other new cameras from here on out, unless they write older RAW formats or DNG.
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Santa: I haven't noticed the problem you're talking about, although i haven't set the autofocus to the * button, i've just kept the autofocus on button performing that function. Is having autofocus on the * button rather than the AF on easier for you? I experimented a little with shooting in low light where focus couldn't be achieved or some fast action of my girlfriend playing soccer but in both cases there wasn't a delay in AF servo.
Ray: I guess i was referring more to the difference between the rebel and the 40d which is probably pretty obvious to anyone who has held either, but their is a significant difference between the 20d and 40d. I bought the 40d because i smashed the 20d in a rock climbing fall (pretty stupid) so mine isnt a very good comparison anymore because its pretty beat up!
Misirlou: I had never used canon raw converter before and was a little sad cuz it is definilty not as nice as ACR. I didn't realize until i got it home that it wasn't going to be compatible...grrrrrr. I was considering getting lightroom and i guess now i have a reason better than just wanting it .
Cheers all!
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Misirlou: I had never used canon raw converter before and was a little sad cuz it is definilty not as nice as ACR. I didn't realize until i got it home that it wasn't going to be compatible...grrrrrr. I was considering getting lightroom and i guess now i have a reason better than just wanting it .
Cheers all!
[a href=\"index.php?act=findpost&pid=148744\"][{POST_SNAPBACK}][/a]
But you don't have to use DPP. Go to the Adobe site and dowload the latest version of DNG Converter, which is free. Point it to a directory of 40D CR2 files, and it will make a new copy of each in DNG format. Then load the DNGs in any version of Adobe Camera RAW that you would like. Sure, it means an extra step, but it costs nothing. Later on when you get a newer version of Lightroom or Photoshop, you can go back and work with the original CR2s, if that's what you prefer.
On the other hand, a lot of people say DPP is the sharpest and cleanest RAW converter for Canon formats that you can use. It's clearly not as convenient as Lightroom, but you can't argue with the price.
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Thanks Misirlou, im so happy to have acr back! Im pretty happy with how acr renders the images, even if dpp is better ill stick with acr as it is fast and easy for me to use.
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I traded my 20D in for a 40D about 4 weeks ago. The image quality is definitely better, however, the best surprise was how much quieter the shutter is on the 40D. No more slapping sound.
Initially, LR didn't support the 40D and I played with Canon's DPP that came with the camera. Yuck!!!! A couple of weeks ago Adobe released an update for PS CS3 and LR that reads 40D RAW files. Now I'm back on track with my workflow using LR. It is sooooooo much better than DPP.
I already sold my 2 year old Canon 1Ds MkII and I'm on the wait list for a new 1Ds MkIII. That will complete my DSLR body upgrades for a while.
Happy Shooting!
Bud James
North Wales, PA.
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I traded my 20D in for a 40D about 4 weeks ago. The image quality is definitely better, however, the best surprise was how much quieter the shutter is on the 40D. No more slapping sound.
[{POST_SNAPBACK}][/a] (http://index.php?act=findpost&pid=148797\")
You might like to have a look at Bob Atkins' review at [a href=\"http://www.bobatkins.com/photography/digital/canon_eos_40D_review_1.html]http://www.bobatkins.com/photography/digit...D_review_1.html[/url]
Bob does a direct comparison of the 40D with the 20D. It's clear that the 40D offers a whole raft of improvements over the 20D, including a quiter shutter.
However, image quality improvement over the 20D is not as definite as you imply. It's rather subtle and only really discernible on test charts. Noise is only marginally less and then only when you have the 40D's noise reduction on, which is a new feature. Dynamic range is also only marginally greater.
I say this not to dampen your enthusiasm but to get the facts straight.
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I find it quite interesting that canon has come up with a camera that is, it seems, better than the original 1ds in all respects except ruggedness of body. At the time the 1ds was seen as a great camera well worth the 8 grand it cost. Now, what 3 years later, this little thing comes along at a fraction of the price with a better screen, better high iso, 14 bit processing etc etc. Thats quite impressive in my mind.
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However, image quality improvement over the 20D is not as definite as you imply. It's rather subtle and only really discernible on test charts. Noise is only marginally less and then only when you have the 40D's noise reduction on, which is a new feature. Dynamic range is also only marginally greater.
I say this not to dampen your enthusiasm but to get the facts straight.
[{POST_SNAPBACK}][/a] (http://index.php?act=findpost&pid=148802\")
Bob did not say that the 40D image quality improvement is "only really discernible on test charts". What he said was "you'd need to make a pretty large print or do some very heavy cropping to notice the difference," which are two things I do on a regular basis. I assume many others do the same. Bob also said "In just about every respect the EOS 40D technically outperforms the EOS 30D." That's the straight facts.
You might want to look at this review:
[a href=\"http://www.dpreview.com/reviews/canoneos40d/page20.asp]http://www.dpreview.com/reviews/canoneos40d/page20.asp[/url]
According to that one, you can recover 11 stops of information from a 40D RAW file. I'm getting noticably more dynamic range out of my 40D than I can from my 20D.
Call it "Marginal" if you want, but image quality is improved enough that I'm giving my mom my 20D (considerd converting it to IR, but she really needs an SLR right now). I wouldn't say the 40D makes the 20D or the 30D obsolete, but the 40D is a more capable camera than either. You'll have to decide for yourself if that extra capability is worth the expense or not.
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Bob did not say that the 40D image quality improvement is "only really discernible on test charts". What he said was "you'd need to make a pretty large print or do some very heavy cropping to notice the difference," which are two things I do on a regular basis. I assume many others do the same. Bob also said "In just about every respect the EOS 40D technically outperforms the EOS 30D." That's the straight facts.
You might want to look at this review:
http://www.dpreview.com/reviews/canoneos40d/page20.asp (http://www.dpreview.com/reviews/canoneos40d/page20.asp)
According to that one, you can recover 11 stops of information from a 40D RAW file. I'm getting noticably more dynamic range out of my 40D than I can from my 20D.
Call it "Marginal" if you want, but image quality is improved enough that I'm giving my mom my 20D (considerd converting it to IR, but she really needs an SLR right now). I wouldn't say the 40D makes the 20D or the 30D obsolete, but the 40D is a more capable camera than either. You'll have to decide for yourself if that extra capability is worth the expense or not.
[a href=\"index.php?act=findpost&pid=148891\"][{POST_SNAPBACK}][/a]
The 30D (what I have) comparison is shows very weak improvement. Unfortunately their test scene doesn't really have the stuff I'm mostly interested - ie. shadow performance at low ISOs and long exposures, and dynamic range. The test numbers with charts promise about 0.5 EV improvement over 30D, which isn't worth the few hundred euros it will cost to upgrade - especially since I do digital blending from multiple exposures on all tough scenes. The improved reach in shadows would be nice, but since it's in the last bits there are very few levels of usable information to begin with.
As 40D has no features other than sensor cleaning that I'd really like, it seems like I'll hold on for now.
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The 30D (what I have) comparison is shows very weak improvement. Unfortunately their test scene doesn't really have the stuff I'm mostly interested - ie. shadow performance at low ISOs and long exposures, and dynamic range. The test numbers with charts promise about 0.5 EV improvement over 30D, which isn't worth the few hundred euros it will cost to upgrade - especially since I do digital blending from multiple exposures on all tough scenes. The improved reach in shadows would be nice, but since it's in the last bits there are very few levels of usable information to begin with.
As 40D has no features other than sensor cleaning that I'd really like, it seems like I'll hold on for now.
[a href=\"index.php?act=findpost&pid=148895\"][{POST_SNAPBACK}][/a]
A reasonable approach.
Before I hand my 20D over to my mom, I may run a series of tests on my own. I could shoot an indoor scene at night at assorted ISOs, and then just put the RAW files on my website. Interested parties could then play with them ad infinitum.
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I find it quite interesting that canon has come up with a camera that is, it seems, better than the original 1ds in all respects except ruggedness of body. At the time the 1ds was seen as a great camera well worth the 8 grand it cost. Now, what 3 years later, this little thing comes along at a fraction of the price with a better screen, better high iso, 14 bit processing etc etc. Thats quite impressive in my mind.
[a href=\"index.php?act=findpost&pid=148837\"][{POST_SNAPBACK}][/a]
Its funny you should mention that, i thought very hard about buying a used 1ds from ebay instead of the 40d as they can be had for 1800-1900 on ebay right now. It seems to me that the weather sealing, better autofocus, and higher resolution would be worth the extra 500 or so dollars, but i did a bunch of comparisons with data on dpreview and it seemed like despite the higher resolution the IQ of the 1ds just wasn't up to the standards of current bodies, it seemed to have pretty high noise, even at low iso's and just wasn't quite as sharp despite having more pixels. That coupled with the slow frame speed, shallow buffer, and extra size, that would be in the way for how i use my camera, and i bought the 40d instead. I bet for alot of people with different needs though, a used 1ds would be a great bargain at those prices.
im headed out to shoot, have a great day guys and gals
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Ok, I have done some shooting for anyone who might be interested in advanced pixel peeping of the 40D vs 20D.
I took a series of 12 shots of the same (dismal) scene with both my 20D and my 40D using the same lens (the 50 1.4). The series was designed to "worst case" everything. The lighting was a particularly heinous shade of tungsten, and very dim. I used autofocus, with aperture priority set to f/8 for all shots. I made one frame from each camera at every possible ISO. All noise reduction was turned off on both cameras, and I turned off the highlight feature on the 40D. About the only positive thing I did was place each camera on the same tripod, and shoot with mirror lockup.
I converted each RAW file to DNG, so there is zero processing, and everyone with any version of ACR or Lightroom can play. I compressed all 12 DNG files into a 100M zip file.
Does anyone want this? Let me know, and we'll work out a way for you to get the zip. What is my impression of the results? I don't have one. I don't spend time pixel peeping myself. But you're more than welcome to my files.
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Are there any comparisons to the Nikon D80 posted anywhere?
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Are there any comparisons to the Nikon D80 posted anywhere?
[a href=\"index.php?act=findpost&pid=148943\"][{POST_SNAPBACK}][/a]
Just the D200 on the dpreview site.
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Bob did not say that the 40D image quality improvement is "only really discernible on test charts".[a href=\"index.php?act=findpost&pid=148891\"][{POST_SNAPBACK}][/a]
No, that's what I said after reading Bob's review and others and having compared the resolution of my 20D with my D60 and the 5D with the 1Ds2 and so on. If I'm wrong, I'm wrong. Show me I'm wrong and I'll admit it.
If you are in the habit of making 6ftx4ft enlargements or heavily cropping telephoto shots taken with a 200mm lens when you should ideally be using a 600mm lens, then you will of course notice a slight resolution improvement in the 40D shots. But in order to demonstrate such improvements, Bob had to display a 200% crop of a test chart.
When a section of a 10mp image is viewed on the average computer monitor at 200% enlargement and from a distance of 12" or so, the detail you see is equivalent to viewing a 6ft x 4ft print (or thereabouts) from the same distance.
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Its funny you should mention that, i thought very hard about buying a used 1ds from ebay instead of the 40d as they can be had for 1800-1900 on ebay right now. It seems to me that the weather sealing, better autofocus, and higher resolution would be worth the extra 500 or so dollars, but i did a bunch of comparisons with data on dpreview and it seemed like despite the higher resolution the IQ of the 1ds just wasn't up to the standards of current bodies, it seemed to have pretty high noise, even at low iso's and just wasn't quite as sharp despite having more pixels. That coupled with the slow frame speed, shallow buffer, and extra size, that would be in the way for how i use my camera, and i bought the 40d instead. I bet for alot of people with different needs though, a used 1ds would be a great bargain at those prices.
im headed out to shoot, have a great day guys and gals
[a href=\"index.php?act=findpost&pid=148932\"][{POST_SNAPBACK}][/a]
I can think of only one good reason, and one not-so-good reason, why I might prefer a 2nd hand 1Ds at a bargain price to a brand new 40D.
(1) The possibility of better wide-angle coverage, especially if I already owned some expensive wide-angle lenses.
(2) The capacity to use autofocus at f8 when using a 1.4x converter with an f5.6 lens like the 400/5.6 or 100-400 IS zoom.
However, personally these reasons would not be sufficient for me. I think I would prefer a 40D if I had to make a choice.
In fact, the 2nd reason is not only a poor reason, it's no reason at all. A 400mm lens with 1.4x extender on the 1Ds gives a reach of 560mm with some inevitable loss of image quality. A 400mm lens on the 40D gives a reach of 640mm with no loss of quality, so we are really left with just the wide angle issue and how important that is to you.
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Ok, I have done some shooting for anyone who might be interested in advanced pixel peeping of the 40D vs 20D.
I took a series of 12 shots of the same (dismal) scene with both my 20D and my 40D using the same lens (the 50 1.4). The series was designed to "worst case" everything. The lighting was a particularly heinous shade of tungsten, and very dim. I used autofocus, with aperture priority set to f/8 for all shots. I made one frame from each camera at every possible ISO. All noise reduction was turned off on both cameras, and I turned off the highlight feature on the 40D. About the only positive thing I did was place each camera on the same tripod, and shoot with mirror lockup.
I converted each RAW file to DNG, so there is zero processing, and everyone with any version of ACR or Lightroom can play. I compressed all 12 DNG files into a 100M zip file.
Does anyone want this? Let me know, and we'll work out a way for you to get the zip. What is my impression of the results? I don't have one. I don't spend time pixel peeping myself. But you're more than welcome to my files.
[a href=\"index.php?act=findpost&pid=148938\"][{POST_SNAPBACK}][/a]
I would really like this. I'm only interested in the 100 ISO shots. I hope auto-focusing isn't off, as that would unnecessarily complicate the comparison.
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I would really like this. I'm only interested in the 100 ISO shots. I hope auto-focusing isn't off, as that would unnecessarily complicate the comparison.
[a href=\"index.php?act=findpost&pid=148978\"][{POST_SNAPBACK}][/a]
feppe,
Since you're only interested in ISO 100, I'll just pull out those files and zip them seperately. I'll put them on my web site tonight, and then post here so you'll know when they're available.
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Let the pixel peepers wage on with their intellectual debate! I say, go look at some prints to draw your own conclusions.
As a former 10D, 20D, 1D MkII and 1Ds Mk II owner, I am very impressed with the quality and color from my new 40D. Compared to the 20D, the 40D is a very worthwhile upgrade. Not only because of improved image quality, but faster focusing, and faster motor drive, but because of the whisper quiet shutter.
My 2 cents.
Bud James
North Wales, PA
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Let the pixel peepers wage on with their intellectual debate! I say, go look at some prints to draw your own conclusions.
As a former 10D, 20D, 1D MkII and 1Ds Mk II owner, I am very impressed with the quality and color from my new 40D. Compared to the 20D, the 40D is a very worthwhile upgrade. Not only because of improved image quality, but faster focusing, and faster motor drive, but because of the whisper quiet shutter.
My 2 cents.
Bud James
North Wales, PA
[a href=\"index.php?act=findpost&pid=149035\"][{POST_SNAPBACK}][/a]
That's fine. I'm happy for you. I'm just rather skeptical when people make claims that cannot be demonstrated or shown through the internet by people who are expert in testing cameras.
You must realise that most people do not have the opportunity to compare prints of identical scenes from different cameras, so why suggest it?
No-one is doubting that the 40D has many new features that are worthwhile; faster frame rate, supposedly more accurate focussing, live view, ISO bracketing etc.
It's just that better image quality is something I haven't noticed yet, except at the pixel-peeping level at 200% enlargement.
However, I believe the saturation of red has been toned down a little on the 40D and that's the only difference I notice when I compare the 40D image of the house with the 30D image of the same poster of the house at Imaging Resources, using their comparator.
You'll have to forgive me if I think some of you might be engaged in some wishful thinking on the issue of improved image quality.
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Let the pixel peepers wage on with their intellectual debate! I say, go look at some prints to draw your own conclusions.
As a former 10D, 20D, 1D MkII and 1Ds Mk II owner, I am very impressed with the quality and color from my new 40D. Compared to the 20D, the 40D is a very worthwhile upgrade. Not only because of improved image quality, but faster focusing, and faster motor drive, but because of the whisper quiet shutter.
[{POST_SNAPBACK}][/a] (http://index.php?act=findpost&pid=149035\")
I've seen plenty of claims about greatly improved IQ, but I don't see that in any of the unprocessed full-sized JPEGs I've seen. Dynamic range is improved by 0.5 stops according to pixel peepers, whoop de doo. Any benefits promised by 14-bit processing are nowhere to be seen. And the resolution increase over 30D is marginal. But I'll wait for the RAWs to pass final judgment on IQ. I was very excited after I saw the initial hands-on tests claiming it to be as good as 1-series Canons of the previous generation, but it appears that it was mainly cognitive dissonance from people who made an expensive upgrade for marginal gains (I hope nobody from the MFDB forum reads this ), or who actually like the new features.
I couldn't care less about better focusing, faster drive or quieter shutter. Or LiveView; I mean, seriously? Since when were dSLRs designed for the lowest common denominator? Oh, right, since when Canon decided a frigging direct print button is more in demand than an MLU button. And if that's actually the case in the trenches, we really have something to be worried about. And since Canon (and Nikon) is still stuck in the 35mm SLR setup without making real UI improvements - such as programmable bracketing, 30+ sec exposures without dunking €100 on a stupid remote, fully parametric exposure settings, and multiple programmable presets or coming up with something which is actually new, such as [a href=\"http://audioblog.fr/archives/2007/10/02/adobe-dave-story-future/]this[/url] or this (http://www1.cs.columbia.edu/CAVE/projects/jitter_camera/jitter_camera.php) -, and still refusing to put the goddam MLU button, I see little real improvement for myself. I'm getting increasingly frustrated at the dSLR manufacturers who seem to be resting on their laurels, and milking the cow that is price discrimination, marginal improvements and planned obsolescence. I just hope Fuji, Foveon or a black horse comes in and starts shaking things real soon, otherwise we'll be stuck with this same old for another few generations.
Whew. I feel much better now.
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I couldn't care less about better focusing, faster drive or quieter shutter. Or LiveView; I mean, seriously? Since when were dSLRs designed for the lowest common denominator?
Whew. I feel much better now.
[a href=\"index.php?act=findpost&pid=149079\"][{POST_SNAPBACK}][/a]
Glad you had the "[/rant]" disclaimer at the end of your post - the 4 things you listed are why it is getting rave reviews from wildlife shooters, for example at Naturescapes. Yet they are far from lowest common denominator photographers
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A faster frame rate will always be useful for hand-held HDR shots with CS3's much improved auto-alignment feature. Faster and more accurate focussing is likely to result in a smaller proportion of one's shots being misfocussed and Live View might facilitate more accurate manual focussing.
The fact that pixel count has been increased (compared with the 30D) without compromising image quality which, at the pixel-peeping level actually appears to be very slightly better, is some comfort but nothing to shout about.
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Glad you had the "[/rant]" disclaimer at the end of your post - the 4 things you listed are why it is getting rave reviews from wildlife shooters, for example at Naturescapes. Yet they are far from lowest common denominator photographers
[a href=\"index.php?act=findpost&pid=149110\"][{POST_SNAPBACK}][/a]
More pertinent disclaimer was the italiziced "for me" claim there: the features don't matter to me, but I concede that there are a lot of shooters who do benefit from those. This is (mostly) a landscape forum, so I feel my consternation is appropriate.
A faster frame rate will always be useful for hand-held HDR shots with CS3's much improved auto-alignment feature. Faster and more accurate focussing is likely to result in a smaller proportion of one's shots being misfocussed and Live View might facilitate more accurate manual focussing.
The fact that pixel count has been increased (compared with the 30D) without compromising image quality which, at the pixel-peeping level actually appears to be very slightly better, is some comfort but nothing to shout about.
I've done some hand-held stitch-jobs and digital blending, and don't see how higher frame rate would ease this at all: you still need to align the shots. Focusing is not an issue for me 90% of the time since I focus manually, as I hope most landscape shooters do. Live View will also facilitate higher noise levels, although I'm not at all convinced that noise is anything to be worried about - but how does manual focusing benefit from squinting at a low-res LCD screen?
Actually, the only marginally increased pixel count gives me some hope that Canon is concentrating on other IQ factors than the headline megapixel figure. But after reading the several reviews, it appears that the claimed IQ improvement by marketroids from higher DR and 14-bit processing is even more marginal than the megapixel increase.
Again, nice features, but are they worth several hundred for me? Hell no. I don't need to have the latest and the greatest - my 30D made great photos half a year ago, and it still does. And I can buy a nice prime with that money, which would go much farther in increasing the IQ of my shots - not to mention it doesn't become "obsolete" again in 2 years.
That is until Canon comes up with a new range of digital lenses with 1DsIV Mark my words.
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I've done some hand-held stitch-jobs and digital blending, and don't see how higher frame rate would ease this at all: you still need to align the shots.[a href=\"index.php?act=findpost&pid=149146\"][{POST_SNAPBACK}][/a]
The faster frame rate should result in less misalignment (without tripod) which is easier to correct. CS3E also has a stacking feature which produces considerable reduction in noise from 5 or so stacked and auto-aligned images. The more the better. A faster frame rate should enable one to shoot more images hand-held with less misalignment and get greater noise reduction without loss of resolution.
but how does manual focusing benefit from squinting at a low-res LCD screen?
I presume the image on the LCD screen in Live View mode can be greatly magnified just as the shot image can on playback. The 40D LCD screen is also impressively large.
the only marginally increased pixel count gives me some hope that Canon is concentrating on other IQ factors than the headline megapixel figure. But after reading the several reviews, it appears that the claimed IQ improvement by marketroids from higher DR and 14-bit processing is even more marginal than the megapixel increase.
Actually, I'm all in favour of increased pixel count as long as noise and dynamic range does not suffer. That's the challeng when any manufacturer increases pixel count. Canon has done a reasonable job with the 40D in maintaing low noise and high dynamic range whilst increasing pixel count by 25%.
Unfortunately, a 25% increase is not enough for a noticeable increase in resolution, beyond the pixel peeping level. One needs at least a 50% increase. A 12mp 40D would have been a much more attractive proposition as an upgrade to the 20D or 30D.
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That's fine. I'm happy for you. I'm just rather skeptical when people make claims that cannot be demonstrated or shown through the internet by people who are expert in testing cameras.
You must realise that most people do not have the opportunity to compare prints of identical scenes from different cameras, so why suggest it?
No-one is doubting that the 40D has many new features that are worthwhile; faster frame rate, supposedly more accurate focussing, live view, ISO bracketing etc.
It's just that better image quality is something I haven't noticed yet, except at the pixel-peeping level at 200% enlargement.
However, I believe the saturation of red has been toned down a little on the 40D and that's the only difference I notice when I compare the 40D image of the house with the 30D image of the same poster of the house at Imaging Resources, using their comparator.
You'll have to forgive me if I think some of you might be engaged in some wishful thinking on the issue of improved image quality.
[{POST_SNAPBACK}][/a] (http://index.php?act=findpost&pid=149056\")
Well, I don't claim to be an "expert camera tester," nor do I particularly rely on them to guide my choices. I only care about how the equipment works for me. In my experience, a 40D image looks pretty similar to a 20D one on a per pixel basis, but the 40D has a lot more pixels. As far as I'm concerned, that's better.
The 40D has plenty of new features, most of which I expect to use. I never shoot JPGs, so I'm not especially entranced by Picture Styles, but I suppose there are others who might be excited.
Is the 40D better enough to merit replacement of anyone else's 20D? I don't have the foggiest idea. Depends on how you use your cameras, how much you like to spend on them, etc. I've certainly never claimed a 40D is as good as a full-frame camera, and it doesn't matter to me because I can't afford a full frame camera anyway.
My wife bought me a 40D, and I prefer it to my old 20D. That's all I can say.
I did shoot a series with both my 20D and my 40D at avery available ISO. I converted the RAWs to DNG, and zipped up the whole set, which you may find at:
[a href=\"http://www.wesandcarol.com/Files/PixelPeeps.zip]Humongous Zip File[/url]
The whole zip is over 100M, so I'm warning you that it will probably take a good long time to download.
I ran the AcrCalibrator script on both cameras, and here are my suggested settings for ACR:
40D
shadow tint -2
red hue -18
red sat 21
green hue -4
green sat 8
blue hue 6
blue sat -5
20D
shadow tint 0
red hue -16
red sat 20
green hue -7
green sat 17
blue hue 4
blue sat -6
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Thanks misirlou, coming at a nice 400+kB/sec!
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Thanks misirlou, coming at a nice 400+kB/sec!
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It uploaded a lot slower than that!
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That's fine. I'm happy for you. I'm just rather skeptical when people make claims that cannot be demonstrated or shown through the internet by people who are expert in testing cameras.
You must realise that most people do not have the opportunity to compare prints of identical scenes from different cameras, so why suggest it?
No-one is doubting that the 40D has many new features that are worthwhile; faster frame rate, supposedly more accurate focussing, live view, ISO bracketing etc.
It's just that better image quality is something I haven't noticed yet, except at the pixel-peeping level at 200% enlargement.
However, I believe the saturation of red has been toned down a little on the 40D and that's the only difference I notice when I compare the 40D image of the house with the 30D image of the same poster of the house at Imaging Resources, using their comparator.
You'll have to forgive me if I think some of you might be engaged in some wishful thinking on the issue of improved image quality.
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Ray,
So I think that it's a real simple answer for you - don't buy a 40D.
Bud
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Ray,
So I think that it's a real simple answer for you - don't buy a 40D.
Bud
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Bud,
I never had a question. I've done my research and was merely correcting the original poster's statement which implied there was a definite improvement in the 40D's image quality compared with the 20D.
I won't be buying a 40D because my main camera is the 5D. My 20D is now used quite infrequently; mostly when I want the extra reach it gives me with my longest lens.
There is a noticeable and definite resolution improvement in the 20D image compared with a 5D image which has been cropped to the same FoV as the 20D image, after using the same lens with both cameras from the same position, and that's because the cropped 5D image is just 4.7mp.
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(2) The capacity to use autofocus at f8 when using a 1.4x converter with an f5.6 lens like the 400/5.6 or 100-400 IS zoom.
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Ray,
I have a 100-400 and a 1.4x teleconverter and the 40d does a pretty good job of focusing with this combo with the pins on the TC taped to allow AF. i love shooting birds and since they are generaly far away and small, the crop factor, the 400mm and the 1.4x make it much easier. In good lighting its fine, in poor lighting it will sometimes hunt, but its better than the 20d in this regard. Come to think of it, i haven't tried untaping the pins, i wonder if it would work on the 40d?
Chris
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thanks for answering the question i was going to ask
if my old EOS 3 (peacefully resting in the closet) could autofocus at f8, why can't all new digital Canons do the same?
but then, why does Canon offer an 800mm lens instead of up-dating the 100-400?
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Come to think of it, i haven't tried untaping the pins, i wonder if it would work on the 40d?
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I've read on other forums that it doesn't. Is there some technological problem here due to the size of the sensor? It seems a bit odd to me. If focussing accuracy and speed is increased on the 40D, then one would think it would be increased proportionally under all lighting conditions to the extent that at f8 autofocus becomes acceptable good if not always brilliant.
I can't remember, do any of the Nikon cropped format cameras have autofocussing at f8?
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if my old EOS 3 (peacefully resting in the closet) could autofocus at f8, why can't all new digital Canons do the same?
but then, why does Canon offer an 800mm lens instead of up-dating the 100-400?
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Well, the 800/5.6 is filling a gap between the 600/4 and the ridiculously expensive and heavy 1200/5.6.
What I would like to see from Canon is a whole range of lightweight f5.6 telephoto IS lenses starting from 400mm. The current 400/5.6 needs updating because it has no IS. The 400/2.8, 500/4 and 600/4 all have IS but are too heavy.
I can understand in the days of film, f5.6 long telephoto lenses would have been of limited use. They would often require use of high ISO film to get the required shutter speed, but most of Canon's DSLRs produce acceptably sharp and noise free images at ISO 800, which was not the case with ISO 800 film.
The 100-400 IS is marred because it's noticeably less sharp at f5.6 than at f8. It should be possible to produce prime telephoto lenses that are at least as sharp at their maximum aperture of f5.6 as at f8, if not sharper.
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feppe,
I own a 40d, I would never in a million years thought i would find the live view of much use, especially without autofocus (if it had that it would be great for scrum shots). That being said, it makes manual focusing much better. If all landscape shooters should be manual focusing, as you say, then this is a big help. The ability to zoom in to 10x the normal view and fine tune things is excellent, and far more acurate that the viewfinder, even on the "low-res LCD screen". I would suggest you try it, you may not like it, you might. I didn't think it would be useful but it is.
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I pixelpeeped misirlou's 20D vs 40D RAWs (thanks for the effort, misirlou!). I only looked at the 100 ISO as that's where I do 99% of my shooting. This is the first time I've really done anything like this, so keep that in mind when reading this.
I couldn't find any evidence of increased dynamic range, but the scene lacks deep shadows with details. The colors are very slightly different, and the ColorChecker shows most difference in the fleshy tone. The stucko wall in the sample has quite a different tone, and it's somewhat flesh-colored. Hard to tell if it's more "accurate" with real flesh tones, but I'd imagine that was the reason for changing it. Whether that was another optimization for Japanese or Caucasian skin tones is a matter for portrait photographers to decide.
The biggest difference I saw was in detail. The RAWs from 40D shows quite a bit more detail than 20D, more so than I expected from the modest resolution increase. But when I did capture and output sharpening, the difference was almost unnoticeable at 100%! As the end-result is the only thing that matters to me, this suggests that Canon hasn't made much improvement despite the increased resolution and apparent detail rendition improvement with unprocessed RAWs. I haven't printed out anything, yet.
I was quite shocked at the un-sharpened detail increase, and was already re-considering my stance. But after doing proper sharpening the difference all but disappeared.
What I make of this: still looking for proof of dynamic range increase and shadow noise improvement. If that's not forthcoming, I'll hold on to my 30D.
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The biggest difference I saw was in detail. The RAWs from 40D shows quite a bit more detail than 20D, more so than I expected from the modest resolution increase. But when I did capture and output sharpening, the difference was almost unnoticeable at 100%! As the end-result is the only thing that matters to me, this suggests that Canon hasn't made much improvement despite the increased resolution and apparent detail rendition improvement with unprocessed RAWs. I haven't printed out anything, yet.
I was quite shocked at the un-sharpened detail increase, and was already re-considering my stance. But after doing proper sharpening the difference all but disappeared.
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Since I have broadband in my present circumstances, I also downloaded Misirlou's comparison images. I sort of half expected there would be a difference in exposure due to a different ISO accuracy between the two cameras, but I see that Misirlou has compensated for that. The main difference is that the 40D image comes out slightly more contrasty with the same ACR settings. At least the shadows are slightly darker.
The surprise to me is not that the 40D shows greater detail. There is slightly greater accutance in the 40D image but there's also something odd going on considering these shots were taken with the same lens. There's a noticeably greater difference in resolution at the far left edge than there is in the centre.
In fact if the difference in resolution at the far left edge extended across the entire image, I would consider that a worthwhile increase in resolution for the 40D that could not be compensated by any amount of sharpening.
Could it be the focussing in the 2 shots is slightly different and if so, why should it affect edge resolution more than centre resolution? Could it be Misirlou's 20D sensor just happens to be slightly under par in its performance on the left side, or could it be that the 40D has improved performance at the edge of the sensor which no-one but a pixel-peeper would notice?
The two sets of crops below compare upressed 20D images which are unsharpened, although both images had initial default sharpening in ACR.
In the centre crop I used a bit of gamma correction on the 40D image to lighten it slightly and used a bit of local contrast enhancement on the 20D image to equalise the tonality of the two images as far as possible.
[attachment=3800:attachment] [attachment=3801:attachment]
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Since I have broadband in my present circumstances, I also downloaded Misirlou's comparison images. I sort of half expected there would be a difference in exposure due to a different ISO accuracy between the two cameras, but I see that Misirlou has compensated for that. The main difference is that the 40D image comes out slightly more contrasty with the same ACR settings. At least the shadows are slightly darker.
The surprise to me is not that the 40D shows greater detail. There is slightly greater accutance in the 40D image but there's also something odd going on considering these shots were taken with the same lens. There's a noticeably greater difference in resolution at the far left edge than there is in the centre.
In fact if the difference in resolution at the far left edge extended across the entire image, I would consider that a worthwhile increase in resolution for the 40D that could not be compensated by any amount of sharpening.
Could it be the focussing in the 2 shots is slightly different and if so, why should it affect edge resolution more than centre resolution? Could it be Misirlou's 20D sensor just happens to be slightly under par in its performance on the left side, or could it be that the 40D has improved performance at the edge of the sensor which no-one but a pixel-peeper would notice?
The two sets of crops below compare upressed 20D images which are unsharpened, although both images had initial default sharpening in ACR.
In the centre crop I used a bit of gamma correction on the 40D image to lighten it slightly and used a bit of local contrast enhancement on the 20D image to equalise the tonality of the two images as far as possible.
[attachment=3800:attachment] [attachment=3801:attachment]
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My own guess is that the cameras didn't focus at exactly the same point. I set the central autofocus zone on both cameras to read at the very contrasty border between two patches on the McBeth chart. I bet neither camera picked exactly the same distance. The 40D central focus sensor is noticeably more sensitive than the one in the 20D.
Manual focus might have made for a more consistent test, but I find the 20D to be a real bugger to manually focus in dim light, though the 40D is a little bit better. The 40D has Live View, which should make manual focus a lot more precise when tripod mounted. Oh, wait a minute. Serious photgraphers are not supposed to stoop to such pedestrian frivolities as Live View. Forget I mentioned it.
Now that I think about it, the 50 f/1.4 is probably not at its best at such a close distance. It might be worth repeating on an outdoor scene from a greater distance.
On the other hand, the 40D sensor supposedly has a much improved set of microlenses. It might be possible that the image really is a lot better at the edges simply because of the sensor improvement.
And to get back to my original point, 40D images are superior to 20D images, even without stooping to extreme pixel peeping. At least with my copy of each camera.
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And to get back to my original point, 40D images are superior to 20D images, even without stooping to extreme pixel peeping. At least with my copy of each camera.
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Pity you've not been able to demonstrate it with those sample RAW images you've taken the trouble to post .
The clear resolution advantage of the 40D at the edges of the frame in the ISO 100 shot is a bit of a mystery. Since I'd downloaded all your RAW images initially but hadn't taken the time to examine the other ISOs, I decided I'd check out if this noticeable softness at the edges of the 20D shot at ISO 100 is apparent in the other shots.
Surprise! Surprise! It isn't.
In fact, at higher ISOs the resolution at the edges is even more closely matched than it is at the centre. This could be explained by the fact that 35mm lenses, even on cropped format cameras, are not as sharp at the edges as they are in the centre. Any subtle differences in resolution between the 2 sensors will be more apparent with a sharper lens and almost all lenses are sharper in the centre.
I believe your ISO 100 20D shot is therefore an anomaly and should not be used for resolution comparisons.
In the comparison crops below, at 100% and 200%, I interpolated the 20D shots to the same file size as the 40D shots but did not apply any additional sharpening. Both images have had only the ACR default sharpening of 25 applied during conversion.
I also compared shadow noise in the darkest part of the images by greatly lightening both images with 'levels'. As you can see, both images are as close as matters regarding shadow noise. Conversion settings were: zero shadows and zero contrast with everything else at default.
Now I know that you didn't apply the in-camera noise reduction for theses 40D shots. If you had, then shadow noise would have been marginally improved. However, I would suggest that such improvement is negated by the fact that the 20D has a slightly higher ISO range than the 40D.
You are probably aware that Canon DSLRs have in the past typically understated the ISO values, but this has changed with the 40D. The true ISO range of the 20D is ISO 125 to ISO 4000, compared with actual ISO 100 to 3200 for the 40D. This is reflected in the consistently longer exposure values in all the 40D shots which you've had to apply to avoid underexposure.
Now I'm going to make what I think is a very valid point. If one is going to pixel peep, then do it properly which means taking all pixel-peeping factors into account.
If the 40D has marginally less shadow noise, when noise reduction is turned on, it's a consequence of a slightly longer exposure (more photons impinging upon the sensor). A slightly longer exposure is likely to contribute to greater camera shake and consequently slightly less sharp images which in some circumstances will also negate the slight resolution advantage of the 40D.
For example, if getting clean, sharp images is the goal, then the purpose of increasing the ISO setting is to get either a hand-holdable shutter speed to reduce camera shake, or an adequate shutter speed to freeze subject movement.
At whatever ISO setting you choose, the 40D is at a slight disadvantage here, compared with the 20D. The only circumstances I can think of where it's not at a disadvantage is the taking of stationary subjects on a tripod, as in your RAW samples.
If I need ISO 800 on the 40D, for example, in order to get a hand-holdable shutter speed of 1/25th, I can use 1/30th on the 20D at ISO 800 and the same aperture.
Now the differences in sharpness that on average would result from these differences in shutter speed (and it would have to be an average due to the variable nature of camera shake) would probably be of pixel-peeping proportions, just as the increase in resolution due to the extra 2 megapixels of the 40D is of pixel-peeping proportions. One negates the other, so on balance it ceases to be an issue or an advantage for the 40D, in most circumstances.
In conclusion, I can only repeat that any 'objective' image quality improvements of the 40D are only discernible at the pixel-peeping level, assuming the focussing is not an issue as it appears to be in your ISO 100 shot with the 20D.
Nevertheless, accurate focussing can be very important when using a shallow DoF. A more revealing comparison between these two cameras would be a series of images taken with a high quality lens, say the 85/1.2 at f2.8, focussing on the eyelashes of a model or the pet cat. If the 40D produces consistently sharper images at the point of focus due to more accurate and/or faster focussing, then that's a very worthwhile improvement.
EDGE COMPARISONS
[attachment=3900:attachment] [attachment=3901:attachment]
CENTRE COMPARISONS
[attachment=3902:attachment] [attachment=3903:attachment]
SHADOW NOISE
[attachment=3904:attachment] [attachment=3905:attachment]
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Pity you've not been able to demonstrate it with those sample RAW images you've taken the trouble to post .
In the comparison crops below, at 100% and 200%, I interpolated the 20D shots to the same file size as the 40D shots.
Now I'm going to make what I think is a very valid point. If one is going to pixel peep, then do it properly which means taking all pixel-peeping factors into account.
In conclusion, I can only repeat that any 'objective' image quality improvements of the 40D are only discernible at the pixel-peeping level, assuming the focussing is not an issue as it appears to be in your ISO 100 shot with the 20D
Ok, I'm not sure I understand these apparently contradictory statements, but then I've admitted previously that I'm none too experienced with pixel peeping in the first place. Sorry.
You interpolated the 20D files to the same size as the 40D shots. Why? One can do all sorts of things during interpolation that have an impact on sharpness. My contention is that both cameras produce pretty similar results on a pixel by pixel basis, but a 40D has more of them. If we're going to start interpolating, why aren't we looking at 40D images next to 12MP cameras or something?
If the autofocus in a 20D is more likely to result in innacurately focused pictures, isn't that's a factor in image quality as well? What would you do with a 20D that would mitigate that? Manually focus? At least you can use Live View to manually focus a 40D with some degree of precision.
Why are we interested in testing either a 20D or a 40D with extremely expensive lenses? No 20D is worth very much now, and new 40Ds cost a good bit less than almost all L lenses. Presumably, anyone with a big collection of L lenses wouldn't be very interested in either camera. That's why I tested them with a 50 1.4.
One thing I've noticed recently with the 40D is no patterned structure in the noise in deep shadows like I used to get with the 20D. I'm probably more concerned with noise in most cases than I need to be, given what my prints look like without any extreme measures taken to reduce it. But the 20D nevertheless annoyed me with the banding in deep shadows at high ISO. I've yet to see any discernable banding with the 40D, even without High ISO Noise Reduction turned on.
I've also been favorably impressed with the Highlight Tone Priority feature, although it doesn't work at 100 ISO, and I still don't really understand how it's mechanized in the camera.
I'm afraid I won't be able to demonstrate any of that to you because my 20D is going to live with my mother tomorrow, and will no longer be available for testing.
And I will repeat, if you don't think the 40D produces better images, don't buy one. Nobody's asking you to. The non-sensor related improvements are really where the 40D shines anyway.
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Go easy on each other guys!
I just got back (to the east coast) from two weeks shooting in a bunch of national parks in california and i nearly died of happiness shooting with the 40d! Deep buffer, better viewfinder, improved focusing, all so great. Everything from wildlife to landscape, shore birds to surfing girlfriends. The camera really just made shooting extra fun and easy. I shot with my rebel xt too, usually with a 10-22 mounted and was less happy with it than usual when comparing it to the 40d for usability. i dont know about the pixel peeping but i definitly have more keepers from the 40d. Probably not a fair comparisson but might go to show that all the nice upgrades that canon keeps sending us are worth the money, regardless of IQ...which i still think is better, but maybe only for the sake of continuing the argument
Happy shooting all!
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You interpolated the 20D files to the same size as the 40D shots. Why? One can do all sorts of things during interpolation that have an impact on sharpness. My contention is that both cameras produce pretty similar results on a pixel by pixel basis, but a 40D has more of them. If we're going to start interpolating, why aren't we looking at 40D images next to 12MP cameras or something?
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The best way to compare 2 images is to have them the same size on the screen, otherwise the smaller image will tend to appear sharper even though it's not.
Standard bicubic interpolation actually produces a slight softening effect and usually requires some compensating sharpening, which I did not, however, apply in the above examples.
If one is comparing images at high magnification in true pixel-peeping fashion, it does not help to have a hint of jaggies in the smaller image at 200%. This is also not how one would print images. Interpolating the smaller image to the same file size as the larger image seems to me the most practical and realistic approach. One could go one step further and print out the crops, in which case one would not want to use less than 240ppi for either image and again the images would have to be the same size for proper comparison.
If the autofocus in a 20D is more likely to result in innacurately focused pictures, isn't that's a factor in image quality as well? What would you do with a 20D that would mitigate that? Manually focus? At least you can use Live View to manually focus a 40D with some degree of precision.
If, then yes. But autofocus capability was not part of the test. We don't know if it's an issue which is why I suggested testing with a very sharp lens at wide aperture. Accurate focussing is generally only an issue under certain circumstance such as shallow DoF, poor lighting or a lack of image contrast and detail at the point of focus. If the 40D sometimes outperforms the 20D in this respect, then one could claim improved image quality but only sometimes. This is not quite the same as a blanket statement that 40D image quality is superior to 20D image quality above the pixel-peeping level.
One thing I've noticed recently with the 40D is no patterned structure in the noise in deep shadows like I used to get with the 20D. I'm probably more concerned with noise in most cases than I need to be, given what my prints look like without any extreme measures taken to reduce it. But the 20D nevertheless annoyed me with the banding in deep shadows at high ISO. I've yet to see any discernable banding with the 40D, even without High ISO Noise Reduction turned on.
This sounds like a camera quality control issue. It was what I noticed with my first copy of the 5D; an irregular pattern like a coarse burlap weave in the deepest shadows, usually a sort of burgundy red. I'd never seen such ugly patterns and banding in either my D60 and 20D. I returned the camera to the store and was given another copy. After testing the new copy, I was convinced there was an improvement, but it's still there and I believe it is a characteristic (if not a problem) of both the 1Ds and 5D. There was much discussion of this issue on the old Rob Galbraith forum at the time.
I've also been favorably impressed with the Highlight Tone Priority feature, although it doesn't work at 100 ISO, and I still don't really understand how it's mechanized in the camera.
I've read that shadow noise/detail suffers slightly through the use of that feature. I think there's probably no substitute for proper exposure to the right.
And I will repeat, if you don't think the 40D produces better images, don't buy one. Nobody's asking you to. The non-sensor related improvements are really where the 40D shines anyway.
Well of course. That's a given. I've never claimed there are no worthwhile improvements in the 40D. There obviously are. It's just that it appears to be the case that 'across-the-board' image quality improvement, in respect of both resolution and noise, is very much at the pixel-peeing level. This is a point that I think needs to be stressed.
If there are people out there who are a little disatisfied with the resolution and noise of their 20D or 30D, who perhaps have just bought an A2 printer or Epson 24" wide 7800, they might be disappointed if they bought a 40D partly on the basis that they would get noticeably sharper and more detailed prints with less shadow noise.
This is the matter I'm just trying to clear up. I didn't intend to spoil your fun .
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Well, I guess we'll have to drop the discussion then, or at least I will. We could go around this ring endlessly.
For example, the only way to test autofocus accuracy is to factor in probability. Any system that is subject to random error of any kind has to have its accuracy stated with a defined confidence interval. That would require many, many shots, and I'm not interested.
I'd rather just go out and shoot real pictures. In fact, I still have a couple of nice Rolleiflex 2.8s. One is a Planar and one is a Xenotar. Maybe I'll go compare them.
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Well, I guess we'll have to drop the discussion then, or at least I will. We could go around this ring endlessly.
For example, the only way to test autofocus accuracy is to factor in probability. Any system that is subject to random error of any kind has to have its accuracy stated with a defined confidence interval. That would require many, many shots, and I'm not interested.
I'd rather just go out and shoot real pictures. In fact, I still have a couple of nice Rolleiflex 2.8s. One is a Planar and one is a Xenotar. Maybe I'll go compare them.
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It's not really a matter of going around the ring endlessly but correctly identifying the causes of any perceived improvement in 40D image quality. Doing so is of practical benefit to your skills as a photographer. If 40D images are superior because of more accurate focussing, don't you want to know that?
All the test images I've seen from competent testers, including your own shots, indicate the 14 bit A/D advancement and the extra 2 megapixels of the 40D sensor have a relatively small impact on over-all image quality. In fact, my guess is it was necessary for Canon to move up to 14 bit in order to maintain noise at the 20D level and implement a noise reduction system which doesn't appear to reduce resolution.
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I've also been favorably impressed with the Highlight Tone Priority feature
That surprizes me, because it does nothing useful to the raw data.
The effect of HTP is, that the selected ISO will be lowered by one stop (that's the reason it does not work with ISO lower than 200). However, this is not noted in the Exif data, which shows the selected ISO.
The advantage of HTP with JPEG images is, that it prevents overexposure (or at least reduces the chance) and corrects the brightness by boosting the exposure with 1 EV, except in the very highlights.
The advantage for those recording raw data is, that the brighness of the in-camera display is as high as it would be with the selected ISO, and the two embedded images are boosted by 1 EV with "highlight protection".
As the in-camera histogram is based on the embedded JPEG image, it reflects the corrected exposure.
The disadvantage (a big one IMO) of HTP is, that one can't judge the true exposure because of the manipulated histograms. However, this is meaningful only if the settings make the in-camera histograms appear somewhat like the true raw histograms, which has its own disadvantages.